The U.S. Chemical Safety Board (CSB) found the lack of safe equipment design, ineffective mechanical integrity programs and a failure to investigate near misses contributed to a series of three accidents that occurred over a 33-hour period on Jan. 22 and 23, 2010, at the DuPont Corp.’s Belle, W.Va., chemical manufacturing plant. The final release – of deadly phosgene gas, which was used as a chemical weapon in World War I – resulted in the death of a worker.

Our final report shows in detail how a series of preventable safety shortcomings –including failure to maintain the mechanical integrity of a critical phosgene hose – led to the accidents,” said CSB Chairman Rafael Moure-Eraso. “That this happened at a company with DuPont’s reputation for safety should indicate the need for every chemical plant to redouble their efforts to analyze potential hazards and take steps to prevent tragedy.”

DuPont responded to the final report with a statement that said in part, “As the Chemical Safety Board has recognized, safety is a core value at DuPont and our most important priority. We are fully committed to operating our facilities safely, including our goal of zero – meaning we believe all safety and environmental-related incidents are preventable.”

Approval Follows Public Comment Period

The board voted 4-1 to approve the final report following an extensive public comment period initiated with the release of a draft report on July 7, 2011, in Charleston, W.Va.. In the final report, the board took into consideration all of the comments filed by industry stakeholders, members of the public and other interested parties, some of which resulted in factual corrections or language changes to the draft report.

The report makes numerous safety recommendations. Among them, DuPont was urged to enclose all of its phosgene production and storage areas so that any releases of phosgene will be contained. (The Belle facility subsequently announced it was ceasing phosgene usage in 2011, and had no plans to resume use.)

CSB recommended that OSHA revise the General Industry Standard for Compressed Gases to be at least as effective as the relevant National Fire Protection Association (NFPA) Code 55 (the Compressed Gases and Cryogenics Fluids Code). This would require secondary enclosures for highly toxic gases such as phosgene and provide for ventilation and treatment systems, interlocked failsafe shutdown valves, gas detection and alarm systems, piping system components and similar layers of protection.

CSB also released a safety video titled “Fatal Exposure: Tragedy at DuPont,” based on the investigation, which features an animation depicting the sequence of events leading to the death of a worker when a phosgene hose suddenly burst. The video also explains the causes of two other toxic chemical releases detailed in the report and features comments by Board Member John Bresland, CSB Investigation Team Lead Johnnie Banks and Investigator Lucy Tyler.

DuPont Conducts Own Investigation

DuPont said it conducted its own investigation following the incidents at the Belle facility and already has made a number of changes, not the least of which was the decision to not restart two of the manufacturing processes that used phosgene. The company also conducted a comprehensive safety review at each unit, expanded the process hazards review system and improved employee participation and initiated a new best practice for alarm management.

“There are some points in the final report that we continue to take issue with, and those concerns were noted in comments DuPont submitted to the Chemical Safety Board in response to the draft report release in July, and which are available on the CSB website,” noted the company in its statement.

“Specifically, the 1988 memo included in the report is irrelevant to the 2010 incident, because it refers to an alternate configuration for a unit that was never constructed. In addition, the method of risk assessment reflected in the memo stopped being used by DuPont many years before the 2010 incident and had no bearing in the incident. Our goal is zero – meaning we believe safety- and environmental-related incidents are preventable,” the statement continued.

DuPont started as a gunpowder manufacturer in 1802, and became a major chemical producer within 100 years. “DuPont has had a stated focus on accident prevention since its early days,” said Moure-Eraso. “Over the years, DuPont management worked to drive the injury rate down to zero through improved safety practices.”

Moure-Eraso noted DuPont became recognized across the industry as a safety innovator and leader, adding, “[We] were therefore quite surprised and alarmed to learn that the DuPont Belle plant had not just one but three accidents that occurred over a 33-hour period in January 2010.

“Adoption of the CSB recommendations by OSHA, the Compressed Gas Association and the American Chemistry Council will greatly improve the safe handling of toxic gases nationally and will protect workers from deadly exposures,” he added.